Cannabinoid receptor 1 (CB 1R) expression in rat dental pulp

Abstract

Purpose of the research: Accumulating evidence supports the role of the cannabinoid system in providing an antinociceptive effect in various painful conditions. This effect is mediated through the Cannabinoid receptor 1 (CB1R) expressed on nociceptive afferent nerve terminals. To investigate whether this receptor plays a similar role in dental pain, we studied the presence and distribution of CB1R in rat dental pulp. Pulps from 28 maxillary molars were immunohistochemically stained with an antibody against CB1R. Principal results: Of all tooth specimens, CB1R immunoreactivity (CB1R-ir) was observed to be associated with nerve fibers in radicular pulp and was seen as a continuous network in the subodontoblastic layer. Major conclusion: CB1R was present on nerve fibers in rat dental pulp and possibly plays a role in dental pain mechanisms. © 2012 Japanese Stomatological Society.